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<h1>Version Naming</h1>
<p style="font-weight: bold;">This is the proposal on how versions should be named in the future:</p><p>Rsyslog version naming has undergone a number of changes in
the past. Our sincere hopes is that the scheme outlined here will serve
us well for the future. In general, a three-number versioning scheme
with a potential development state indication is used. It follows this
pattern:</p>
<p>major.minor.patchlevel[-devstate]</p>
<p>where devstate has some forther structure:
-&lt;releaseReason&gt;&lt;releaseNumber&gt;</p>
<p>All stable builds come without the devstate part. All unstable
development version come with it.</p>
<p>The <span style="font-weight: bold;">major</span>
version is incremented whenever something really important happens. A
single new feature, even if important, does not justify an increase in
the major version. There is no hard rule when the major version needs
an increment. It mostly is a soft factor, when the developers and/or
the community think there has been sufficient change to justify that.
Major version increments are expected to happen quite infrequently,
maybe around once a year. A major version increment has important
implications from the support side: without support contracts, the
current major version's last stable release and the last stable release
of the version immediately below it are supported (Adiscon, the rsyslog
sponsor, offers <a href="professional_support.html">support contracts</a> covering all other versions).</p>
<p>The <span style="font-weight: bold;">minor</span> version is
incremented whenever a non-trivial new feature is planned to be added.
Triviality of a feature is simply determined by time estimated to
implement a feature. If that's more than a few days, it is considered a
non-trivial feature. Whenever a new minor version is begun, the desired
feature is identified and will be the primary focus of that major.minor
version. Trivial features may justify a new minor version if they
either do not look trivial from the user's point of view or change
something quite considerable (so we need to alert users). A minor
version increment may also be done for some other good reasons that the
developers have.</p>
<p>The <span style="font-weight: bold;">patchlevel</span> is incremented whenever there is a bugfix or very minor feature added to a (stable or development) release.</p><p>The <span style="font-weight: bold;">devstate</span>
is important during development of a feature. It helps the developers
to release versions with new features to the general public and in the
hope that this will result in some testing. To understand how it works,
we need to look at the release cycle: As already said, at the start of
a new minor version, a new non-trivial feature to be implemented in
that version is selected. Development on this feature begins. At the
current pace of development, getting initial support for such a
non-trivial feature typically takes between two and four weeks. During
this time, new feature requests come in. Also, we may find out that it
may be just the right time to implement some not yet targeted feature
requests. A reason for this is that the minor release's feature focus
is easier to implement if the other feature is implemented first. This
is a quite common thing to happen. So development on the primary focus
may hold for a short period while we implement something else. Even
unrelated, but very trivial feature requests (maybe an hour's worth of
time to implement), may be done in between. Once we have implemented
these things, we would like to release as quickly as possible (even
more if someone has asked for the feature). So we do not like to wait
for the original focus feature to be ready (what could take maybe three
more weeks). As a result, we release the new features. But that version
will also include partial code of the focus feature. Typically this
doesn't hurt as long as noone tries to use it (what of course would
miserably fail). But still, part of the new code is already in it. When
we release such a "minor-feature enhanced" but "focus-feature not yet
completed" version, we need a way to flag it. In current thinking, that
is using a "<span style="font-weight: bold;">-mf&lt;version&gt;</span>" <span style="font-weight: bold;">devstate</span>
in the version number ("mf" stands for "minor feature"). Version
numbers for -mf releases start at 0 for the first release and are
monotonically incremented. Once the focus feature has been fully
implemented, a new version now actually supporting that feature will be
released. Now, the release reason is changed to the well-know "<span style="font-weight: bold;">-rc&lt;version&gt;</span>"
where "rc" stands for release candidate. For the first release
candidate, the version starts at 0 again and is incremented
monotonically for each subsequent release. Please note that a -rc0 may
only have bare functionality but later -rc's have a richer one. If new
minor features are implemented and released once we have reached rc
stage, still a new rc version is issued. The difference between "mf"
and "rc" is simply the presence of the desired feature. No support is
provided for -mf versions once the first -rc version has been released.
And only the most current -rc version is supported.</p><p>The -rc is
removed and the version declared stable when we think it has undergone
sufficient testing and look sufficiently well. Then, it'll turn into a
stable release. Stable minor releases never receive non-trivial new
features. There may be more than one -rc releases without a stable
release present at the same time. In fact, most often we will work on
the next minor development version while the previous minor version is
still a -rc because it is not yet considered sufficiently stable.</p><p>Note: <span style="font-weight: bold;">the
absence of the -devstate part indicates that a release is stable.
Following the same logic, any release with a -devstate part is unstable.</span></p><p>A quick sample:&nbsp;</p><p>4.0.0
is the stable release. We begin to implement relp, moving to
major.minor to 4.1. While we develop it, someone requests a trivial
feature, which we implement. We need to release, so we will have
4.1.0-mf0. Another new feature is requested, move to 4.1.0-mf2. A first
version of RELP is implemented: 4.1.0-rc0. A new trivial feature is
implemented: 4.1.0-rc1. Relp is being enhanced: 4.1.0-rc2. We now feel
RELP is good enough for the time being and begin to implement TLS on
plain /Tcp syslog: logical increment to 4.2. Now another new feature in
that tree: 4.2.0-mf0. Note that we now have 4.0.0 (stable) and
4.1.0-rc2 and 4.1.0-mf0 (both devel). We find a big bug in RELP coding.
Two new releases: 4.1.0-rc3, 4.2.0-mf1 (the bug fix acts like a
non-focus feature change). We release TLS: 4.2.0-rc0. Another RELP bug
fix 4.1.0-rc4, 4.2.0-rc1. After a while, RELP is matured: 4.1.0
(stable). Now support for 4.0.x stable ends. It, however, is still
provided for 3.x.x (in the actual case 2.x.x, because v3 was under the
old naming scheme and now stable v3 was ever released).</p><p style="font-weight: bold;">This is how it is done so far:</p><p>This document briefly outlines the strategy for naming
versions. It applies to versions 1.0.0 and above. Versions below that
are all unstable and have a different naming schema.</p>
<p><b>Please note that version naming is currently being
changed. There is a
<a href="http://rgerhards.blogspot.com/2007/08/on-rsyslog-versions.html">blog
post about future rsyslog versions</a>.</b></p>
<p>The major version is incremented whenever a considerate, major
features have been added. This is expected to happen quite infrequently.</p>
<p>The minor version number is incremented whenever there is
"sufficient need" (at the discretion of the developers). There is a
notable difference between stable and unstable branches. The <b>stable
branch</b> always has a minor version number in the range from 0
to 9. It is expected that the stable branch will receive bug and
security fixes only. So the range of minor version numbers should be
quite sufficient.</p>
<p>For the <b>unstable branch</b>, minor version
numbers always start at 10 and are incremented as needed (again, at the
discretion of the developers). Here, new minor versions include both
fixes as well as new features (hopefully most of the time). They are
expected to be released quite often.</p>
<p>The patch level (third number) is incremented whenever a
really minor thing must be added to an existing version. This is
expected to happen quite infrequently.</p>
<p>In general, the unstable branch carries all new development.
Once it concludes with a sufficiently-enhanced, quite stable version, a
new major stable version is assigned.</p>
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